Because of the dimensional stability required in upholstery fabric, it has been the common practice to utilize woven and warp knitted fabrics for home furnishings, contract, and automotive upholstery applications where the maximum standard for shrinkage in either direction has been established at five percent and the maximum standard for gain in either direction at two percent. However, fabrics of these general constructions are produced from yarns fed from multi-yarn creels or from yarns wound on large beams so that it is generally difficult to readily produce short production runs of a particular style. Also, with these approaches, a relatively long machine down-time is required when changing from one pattern to another in the production of these types of fabrics.
Recognizing the inherent flexibility and resultant advantages of producing upholstery fabric by circular knitting, the broad patterning possibilities it makes possible, and the ability to use novelty yarns in an unlimited range of synthetic and natural fiber combinations, others have proposed to produce upholstery fabric on circular knitting machines. However, as far as is known, these attempts have not met with widely accepted commercial success primarily because the circular knit fabrics have not met the rigid standards for shrinkage and stability so that most of the upholstery fabric currently being produced is either woven on a loom or produced on warp knit equipment.
U.S. Pat. No. 3,115,693 discloses a circular knit fabric which is said to be adapted for use as upholstery and the like. The knit fabric of this patent includes a base yarn forming stitch loops in the wales of successive courses and with the same type of yarn being inlaid along the juncture of the stitch loops of successive courses so that the inlaid yarn appears primarily on the technical back side of the fabric and constitutes the exposed wear surface of the fabric. However, by utilizing the same synthetic fiber type as a yarn component in both the basic knit structure and the lay-in yarn forming the exposed wear surface of the fabric, there is no appreciable contrast between the ( yarns; therefore, the resulting fabric has substantially the same characteristics on both its technical face side and technical back side as the characteristics of the respective base and lay-in yarns utilized in forming the knit fabric. Thus, the knit fabric produced in accordance with this patent does not provide the desired tactile characteristics, appearance and hand of commercially acceptable woven and warp knit upholstery fabrics.